<?php


namespace Part23_CommandMode\Code4;

/**
 * 声明执行操作的接口
 */
abstract class Command
{
    /**
     * @var Receiver
     */
    protected $receiver;

    /**
     * @param $receiver Receiver
     */
    public function __construct($receiver)
    {
        $this->receiver = $receiver;
    }

    abstract function execute();
}